MikeIsOrganic

I've got a nipple that's rounded off and the spoke's also poking through the other side of the nipple (deep section rims, so it would only really be detrimental here i guess). How would I go about removing this nipple? My first thought was to cut the spoke and replace both, but i was told it might damage the hub. I dont know how much I believe that, but I like the idea of asking before figuring out the hard way.

Map tester

Use a pair of ViseGrips to loosen the nipple enough to retract the spoke into the nipple, then use a screwdriver to finish unscrewing the nipple. Replace nipple with new one, and true the wheel.

Retro Grouch 

What kind of condition is the rest of the wheel?

It sounds to me like your spoke is too long since you say it's sticking through the bottom of the nipple. If that's the case, simply replacing the nipple is going to cause the same problem to reccur. If it was my bike, I'd cut the spoke since I'm thinking it's due for a replacement anyway.

Incidentally, I've probably cut a thousand spokes and have never detensioned them first. Zero problems.

Al1943

Have you checked on the availability of that particular spoke? On some deep section aero wheels you can't buy just a few, you have to buy a whole box and that can get really expensive. It just depends on the wheel. I would try to get the nipple off.

orangepaint

I think you'll be fine cutting the spoke. If you don't want to though, try spraying the area with some liquid wrench or WD40 and then unscrewing the nipple with a pair of ultra high torque visegrips.

tellyho

I've had success with vice grips. You might want to file flats on either side of the nipple first, to make it easier.